a(n) = a(n-1)^2 + 2*a(n-2).A113785a(n) = a(n-1)^2 + 2*a(n-2).Terms a(0) =2a(1) =3a(2) =13a(3) =175a(4) =30651a(5) =939484151External referencesoeis: A113785